جستجوی مقالات مرتبط با کلیدواژه "دشت کرمان" در نشریات گروه "آبخیزداری، بیابان، محیط زیست، مرتع"

Groundwater is considered as one of the main resources for drinking water, agriculture and industry. While groundwater is taken as a reserve resource in some areas, in other areas it may be used for supplying potable water due to their easy availability. Moreover, groundwater analysis is an essential factor in maintaining its access. In fact, modeling and predicting the groundwater level play a significant role in preserving the environment, maintaining the balance of the groundwater system, controlling changes in groundwater levels and preventing the escalation of land subsidence. On the other hand, climate change and the decline in groundwater table have been proved to be one of the main causes of land degradation in the past decades. According to Iranian Ministry of Energy, about 7 billion cubic meters of groundwater reservoirs are declining annually. Also, from among 609 plains in Iran, approximately 350 of them are known as the forbidden ones. The increasing number of prohibited plains from 15 wells in 1968 to 199 ones in 2001, and rising the dried plains into 350 ones in 2015 indicate the inappropriate status of water resources in Iran. Meanwhile, the highest amount of water scarcity in underground reservoirs belongs to the second grade Salt Lake as well as the Kerman Plain which has attracted more attentions in recent years as one of the most important plains of this area due to the large decline in its groundwater.

This study set out to model the flow of groundwater in the Kerman plain aquifer under the influence of climate change for the upcoming period, using the GMS model. To this end, HADCM3 model, LARS model and A1B, B1 and A2 scenarios were applied for the investigation of the effects of climate change on aquifer volume and groundwater declines. Finally, having applied four different scenarios, the performance of each management options and the effects of different climate scenarios on the decline of the aquifer were examined.The results of the exponential microscopy indicated a minimum increase in the temperature between 0.59 to 0.86 degrees Celsius and a maximum temperature increase of between 0.56 to 0.85 degrees Celsius. The reported increase in minimum and maximum temperature in the upcoming period is consistent with the results of the studies carried out by Zhang and Nyinger (2005), Mosheh Boani and Merid (2006), Khorshid Doost and Ghavidel Rahimi (2006), Kukchi et al (2006), Yano et al. (2007), and Babayan et al. (2009), where temperature increases have been predicted.Comparison of long-term annual precipitations suggested prospective increase in the rainfall which is consistent with the results of the study conducted by Steel Dani et al. (2008). Moreover, according to the findings of the current study, the lowest amount of precipitation in scenario B1 would occur from 2011 to 2030, which is 10.22 mm more than the base period rainfall. This is while the highest rainfall was expected to occur with a rise of 80/15 mm within the time period of 2011-2030 in scenario A2. As found by the simulation of the groundwater model (GMS), there was an acceptable accuracy for simulating the aquifer of Kerman Plain. In terms of Kerman aquifer quantity, the results suggested, after a steady-state calibration, that RMSE, MAE and ME values were 0.38 m, 0.21 m, and 0.20 m, respectively, showing acceptable accuracy of modeling in the mode was lasting. Having set the proper performance of GMS model, four different scenarios were used to simulate the effect of climate change on the station's level, and its changes were compared with the base period. On the other hand, the decline in water level would be 10.6 -10 in the first scenario. The levels of water decline within climate change scenarios A2, A1B and B1 for were 11.9, 12.36 and 16.22 for the second scenario, 16.41, 16.66 and 17.30 for the third scenario, and 16.65, 16.9 and 18.15 meters for the fourth scenario respectively.

Although climate change directly affects surface water resources changes in major long-term variables such as rainfall, temperature, evapotranspiration and transpiration, it is difficult to determine the relationship between climate change variables and underground water. This study, therefore, attempted to predict the relationship between climate and groundwater levels for the upcoming period. Comparison of long-term annual precipitation indicate in increase in precipitation which is consistent with the results found by Steel Dani et al. (2008). According to the findings of the current study, the calibrated model has acceptable accuracy and the mathematical model can simulate the normal conditions governing the aquifer of Kerman Plain. Having obtained the proper performance of GMS model, four different scenarios were used to simulate the effect of climate change on the station's level, and its changes were compared with the base period. The results showed that an 18-meter water decline would not be expected in such a situation.

Desertification is one of the major challenges of the 21st century. Destruction of water resources, degradation of soil, as well as degradation of vegetation is desertification symptoms. This challenge is not restricted to dry areas, but can be applied in all regions, especially dry, semi-arid, and humid areas. Destroy the affected environment. Therefore, knowledge of its severity can play a significant role in water resource management. In this study, the IMDPA model, which is native to Iran, has been used to predict the desertification of Kerman plain in terms of climate criterion in 1409. Study of climate criteria and its score in the study area is from three indicators of annual precipitation, SPI drought index and drought persistence index. Using predicted precipitation values ​​by LARS-WG model and IMDPA model, the annual precipitation index score was 3.8, the index of drought persistence index was 0.7 and the SPI index was estimated 3.5 points. In the GIS environment, all indicator mapping maps it was drawn up.
The results showed that the annual rainfall index is very severe in the desertification class, the index of drought persistence in the low desertification class, and the SPI drought index in the severe desertification class are located, and the geometric mean of these indicators and their synthesis intensity The desertification of the area on the horizon of 1409 is in severe class. The results of this study can help in the management of desertification processes in the region.

Recognizing of critical zones of groundwater quality is one of the most important issues about researches in water fields. The goal of this study is to determine the spatial and temporal variation of groundwater quality factors such as electrical conductivity and chloride ion contents using the best suited geostatistical estimation in Kerman plain on 10 years period (1996-2006). Also, the best variogeram model and parameters related to model of EC and Cl contents will be determined. Findings of variography analysis for Cl contents of groundwater quality data in the beginning and the end of study period showed that the exponential structure is the best spatial model fitted to this parameter. Thus, its effect range increased from 101700 to 106200 meter and sill contents decreased from 2.246 to 1.698, during 1996 to 2006. The best model fitted to electrical conductivity spatial structure became exponential in 1995-1996 and spherical in 2005-2006. The results of geostatistical analysis show that effect range and sill contents of EC decreased from 79800 to 37500 meter and 0.84 to 0.608, during 1996 to 2006, respectively. Comparing of interpolation methods of groundwater quality data introduced log kriging method as the best approach for Cl and EC zonation maps. Cl zonation maps show an increasing trend of Cl content in all plain areas in 10 years period. Thus, Cl concentration in the input region of plain increased in the range of 3.03-13.01 in 2006.Intensity of Cl content occur in north outlet of plain near well numbers 27, 28, and 33, and Cl critical core of western south of plain near well number 19 show an increasing trend. Our findings showed an increasing in EC content, especially its spatial spreading in west and north outlet of Kerman plain and Kerman city in 10 years period.

Ground water is one of the major resources of fresh water needed for humans, especially in arid areas. It will be seriously threatened in future due to climate change and global warming. The purpose of this study is to examine the effects of climate change on groundwater resources in the Kerman-Baghin plain. Accordingly, climate prediction at 2055 horizon (2065-2046) was used by the atmospheric general circulation model HadCM3 with A2 emissions scenario. Also groundwater table during the years (1986 -2009) and the quality situation (salinity) over the years (2003-2009) were studied. The results of LARS-WG model showed that the average annual rainfall at the 2055 horizon will be reduced about 3.6 mm. Also the annual maximum and minimum temperatures will increase during the 2055 horizon, 2.8°C and 2.8 °C, respectively. Assessing of unit hydrograph and chemograph in Kerman- Baghin plain highlighted a drop in the water table (0.89 meter depletion per year) and increase of aquifer salinity. According to the results of atmospheric general circulation model (HadCM3), this trend in the water table and increase in aquifer salinity expected to be continued.

Determination of groundwater quality is an important issue in watershed management. The aim of this study was to investigate the spatial variability of some properties of Kerman groundwater using geostatistical methods. For this, groundwater quality data including soluble calcium, magnesium, sodium, bicarbonates, sulphates, pH, EC, SAR, TDS and TH for spring season of 2009 were collected. Interpolation analysis was done using Kriging, Co-Kriging, inverse distance weight (IDW) and normal distance weight (NDW) methods. The best interpolation method was chosen through root mean square error, mean absolute error and Pearson’s coefficient parameters. Result showed that the best fitted model for magnesium and pH was linear to sill, whereas for the other groundwater properties the Gaussian’s model was the best. Spatial dependency for bicarbonates and pH was moderate, while for the other ones, strong dependencies were observed. The result also indicated that for all the groundwater properties, Kriging with the Pearson’s coefficient ranging from 0.695 to 0.851 was the best algorithm. In addition to Kriging, the NDW and IDW methods found to be appropriate for the estimation of all the parameters except for EC and TDS. For these two latter ones, additional to Krging, the Co-Kriging method led to suitable estimates. The prepared maps showed that the amounts of bicarbonates and pH were higher at the north and south sides of the study area, respectively. The amounts of the other properties were minimum at the east and north east, while increased toward the west and south west.

Due to the variation of ground water properties in temporal and spatial scale, these properties can not be assumed constant over time and space. This research was conducted to assess spatial and temporal variations of ground water table in Kerman plain during a 10-year period (1375-1385) by using the best geostatistical estimator. Firstly, available statistical resources related to the ground water table of this plain (including 67 wells) were collected. After controlling for quality, accuracy and normality of the data, different interpolation techniques were used including kriging (with and without logarithm), cokriging, inverse distance (with exponents of 1 to 5). The best technique was selected based upon MAE and MBE criteria and provided spatial zonation maps in the beginning and end of the period. Spatial zonning maps were prepared at the beginning and end of the study and ultimately, iso-falling map was provided in Arc GIS 9.1 package. Our findings showed that Gaussian variogram model was the best for spatial structure of these data and inverse distance method with exponents of 5 and 4 were the best interpolation methods in the beginning and end of the period, respectively. Zonation maps showed a falling trend of the ground water level in majority of the plain. Maximum falling data (32 meters), was recorded respectively for the northern outlet of the plain with an effective range of 17 and 62 pizometers and western outlet with an effective range of 8 pizometers. Also, the results showed an upward trend of water, as 7 meters, in effective range of some wells with 50 and 52 pizometers in Kerman city due to being located in sewage and waste water zone of the city.